"It's been out of order all year because she keeps having tantrums and flooding the place."
-- Hermione Granger (CS8)
An out-of-order girls’ bathroom on the second floor; entrance to the Chamber of Secrets and home to Moaning Myrtle.
Upon his first visit to Myrtle's bathroom during his second year, Harry's opinion is that this is the gloomiest, most depressing bathroom he has ever entered. The bathroom's wooden cubicles are worn and ill-maintained, and even the stone sinks are chipped. Like many of Hogwarts' rooms - including the opulent prefects' bathroom - the room is candle-lit, but the candles are in holders rather than a chandelier and there are not enough of them to light the room properly.
The sinks, which form a row under a large cracked and spotted mirror, have copper taps, one of which has a tiny snake scratched on the side. Apparently that particular tap is a complete dud when considered as part of the plumbing; it serves another function. In fact, if given the proper password, that particular tap will glow and spin briefly before the entire sink drops down out of sight to expose the large pipe leading to the Chamber of Secrets (CS9, (CS16).